1. Field of the Invention
The present invention relates generally to medical devices and methods. More particularly, the present invention relates to the structure and use of probes intended to marginally ablate tissue surrounding a tissue cavity.
Treatment of early stage breast cancer typically involves a combination of lumpectomy and whole breast irradiation (WBI). WBI typically utilizes ionizing radiation and can result in short and long-term complications affecting the skin, lungs, and heart. Such risks, when combined with the burden of weeks of daily WBI, drive some women to choose mastectomy instead of lumpectomy and cause up to thirty percent (30%) of women who undergo lumpectomy to stop therapy before completing the full treatment.
One promising alternative to treatment with ionizing radiation is the use of a needle array to deliver radiofrequency energy to the marginal tissue surrounding the cavity left following a lumpectomy. Treatments have been performed with needle arrays intended for treating liver and other solid tissue tumors, and more recently, specialized needle arrays have been proposed for such post-lumpectomy treatments. None of the arrays used or proposed for use thus far have proven to meet all needs and circumstances encountered in when performing marginal cavity tissue ablation.
As such, there remains a need for alternative and improved devices and methods for delivering non-ionizing radiation, such as radiofrequency energy, to deliver precise levels and depths of energy to the tissue immediately surrounding the site of a surgically removed tumor in order to minimize recurrence of the tumor. At least some of these objectives will be met by the inventions described below.
2. Description of the Background Art
US Patent Publication No. 2014/0031810, having common inventors with the present application, describes a probe having an expandable applicator head for radiofrequency ablation of marginal tissue in a tissue cavity. U.S. Pat. No. 6,978,788 describes methods for labeling and ablating a marginal tissue region surrounding a tumor excision site in breast tissue. U.S. Pat. No. 7,942,873 describes an ablation device comprising a needle array and a surrounding sleeve for radiofrequency ablation of marginal tissue in a tissue cavity. Other patents of interest include U.S. Pat. Nos. 4,979,948; 5,562,720; 5,713,942; 5,871,483; 6,123,718; 6,142,993; 6,258,087; 6,491,710; 6,551,310; 7,150,745; 7,344,535; 7,371,231; 7,556,628; 7,632,268; 7,769,432; 7,828,793; and 7,959,631.